Substituted phenylacetic acid compounds

ABSTRACT

Certain substituted Alpha -halo and Alpha mercaptophenylacetic acids and substituted phenylacetic acids having in Alpha -position a sulfur-containing group, a cyano group, or an amino group, their substantially non-toxic esters, salts, and acid amides as well as 5-phenyl substituted 2-imino-4oxothiazolidines and 5-phenyl substituted 2,4-dioxothiazolidines have a high anti-inflammatory, analgesic, and antipyretic activity, low toxicity, and/or a favorable therapeutic index with minor or no side-effects. Preferred compounds of this invention are Alpha ,m-dichloro-p-cyclohexylphenylacetic acids and its esters and salts.

United States Patent 1 Diamond et al.

[4 1 Feb. 18,1975

[ SUBSTITUTED PHENYLACETIC ACID COMPOUNDS [75] Inventors: Julius Diamond, Lafayette Hill;

Norman J. Santora, Roslyn, both of Pa.

[73] Assignee: William H. Rorer Inc., Ft.

Washington, Pa.

[22] Filed: Mar. 10, 1972 [21] Appl. No.: 233,717

Related U.S. Application Data [62] Division of Ser. No. 34,870, May 5, 1970.

[52] U.S. Cl..... 260/515 A, 260/268 R, 260/293.8l, 260/326.3, 260/469 [51] Int. Cl. C07c 63/32, C07c 69/62 [58] Field of Search 260/515 A, 469, 476 R, 260/268 R, 293.81, 326.3

[56] References Cited UNITED STATES PATENTS 3,435,075 3/1969 Glamkowski et al. 260/590 Primary Examiner-James A. Patten Attorney, Agent, or Firm-Erich M H. Radde [57] ABSTRACT a favorable therapeutic index with minor or no sideeffects. Preferred compounds of this invention are a,m-dichloro-p-cyclohexylphenylacetic acids and its esters and salts.

5 Claims, No Drawings SUBSTITUTED PHENYLACETIC ACID COMPOUNDS BACKGROUND OF THE INVENTION 1. Field of the Invention This is a division of application Ser. No. 34,870 filed May 5, 1970.

The present invention relates to a valuable novel substituted phenylacetic acids and more particularly to substituted oz-halophenylacetic acids and substituted phenyl-acetic acids having in a-position a surfur containing group, especially substituted a-mercaptophenylacetic acids, to a process of making such compounds, to pharmaceutical compositions containing the same, and to using such compositions in therapy as anti-inflammatory antipyretic, and analgesic agents.

2. Description of the Prior Art A number of substituted phenylacetic acids and their esters have been tested for their anti-inflammatory, analgesic, antipyretic properties but none of them have been accepted by the medical profession for the treatment of humans or have been marketed by the pharmaceutical industry.

SUMMARY OF THE INVENTION It is one object of the present invention to provide novel and valuable substituted phenylacetic acid compounds of high anti-inflammatory, analgesic, and antipyretic activity, low toxicity and/or a favorable therapeutic index with considerably reduced side-effects.

Another object of the present invention is to provide simple and effective processes of making such novel and valuable substituted phenylacetic acid compounds.

Still another object of the present invention is to provide pharmaceutical compositions containing such novel and valuable substituted phenylacetic acid compounds.

A further object of the present invention is to provide a method of administering such pharmaceutical compositions for their anti-inflammatory, analgesic, and antipyretic activity.

Other objects and advantageous features of the present invention will become apparent as the description proceeds.

In principle the substituted phenylacetic acid compounds according to the present invention are compounds of the following Formula I wherein R is cycloalkyl with 5 to 7 carbon atoms in the cycloalkyl ring such as cyclohexyl, cyclopentyl, cycloheptyl; lower alkyl substituted cycloalkyl such as methyl cyclopentyl, methylcyclohexyl; straightchain or branched alkyl with l to 8 carbon atoms; phenyl; or phenyl substituted by trifluoromethyl CF halogen, lower alkylsulfonyl SO R, nitro, or cyano, such as trifluoromethylphenyl, chlorophenyl, methylsulfonylphenyl, nitrophenyl, cyanophenyl;

isothioureido amino; lower alkylamino NHR and di-(lower alkyl) amino lower alkanoylamino --NH.CO.R; the group of the formula and Y is hydroxyl; or the amido group wherein R'and R are hydrogen, lower alkyl, aralkyl, such as benzyl, or R and R" together with the nitrogen atom to which they are attached, form a heterocyclic ring, such as the pyrrolidino, piperidino, piperazino, or the like heterocyclic ring; and wherein X and Y together with the two carbon atoms to which they are attached, form a heterocyclic ring of the formula or a heterocyclic ring of the formula IIIH C The present invention comprises also the substantially non-toxic, pharmaceutically acceptable esters and salts of the substituted phenylacetic acids of Formula-l wherein Y is hydroxyl. Such esters are, for instance:

a. the esters with lower aliphatic alcohols such as with methanol, ethanol, n-propenol, isopropanol, n-butanol, isobutanol, n-amyl alcohol, isobutylcarbinol, n-hexanol, n-heptanol, n-octanol, monomethylether of ethylene glycol, allyl alcohol, diethylaminoethanol, piperidinoethanol, piperazinoethanol, pyrrolidinoethanol, and other alcohols with 1 to 8 carbon atoms;

b. the esters with slicyclic alcohols and alcohols of the terpene series, such as with cyclopentanol, cyclohexanol, Z-methylcyclohexanol, cyclohexylcarbinol, menthol, borneol, fenchyl alcohol, and other alicyclic alcohols with 6 to 14 carbon atoms;

c. the esters with hydroxyl substituted aryl compounds such as with phenol, cresol, guajacol, and other phenolic compounds with 6 to 14 cabon atoms;

d. the esters with aryl substituted alkanols such as benzyl alcohol, phenylethyl alcohol, anisalcohol, and other aryl substituted alkanols with 7 to 14 carbon atoms;

e. the esters with heterocyclic alcohols such as furfuralcohol and others.

The lower alkyl esters are the preferred esters.

Suitable substantially non-toxic, pharmaceutically acceptable salts of the substituted phenyl acetic acids of Formula I, wherein Y is hydroxy], are, forinstance, the alkali metal or alkaline earth metal salts, such as the sodium, potassium, or calcium salts, the ammonium salts, or the salts with organic bases such as the di-lower alkyl-ammonium salts, for instance, the dimethylammonium salt, the diethylammonium salt, the hydroxy lower alkylammonium salts such as the B-hydroxyethylammonium salt, the piperazinium salt, the piperidinium salt, the lower alkyl benzyl-ammonium salts such as the a-methylbenzylammonium salt, and others.

The term lower alkyl" as used herein and in the claims annexed hereto designates straight-chain or branched alkyl with l to 8 carbon atoms.

In particular the substituted phenylacetic acid compounds of the present invention are a. a-halophenylacetic acids of Formula II c. a-sulfur derivatives of such a-mercaptophenylacetic acids of Formula IV S-derivative R2 Iv such as the corresponding sulfides, disulfides, thiosulfates, xanthates, isothiuronium halides; oxothiazolidines, and the like compounds which serve as latent forms or precursors of the a-mercaptophenylacetic acids of Formula II.

Not only the substituted phenylacetic acids of Formulas II to IV but also their non-toxic salts, the esters, and the amides of said substituted phenylacetic acids have provided to be useful anti-inflammatory, antipyretic, and analgesic agents and are used in reducing the inflammation and pain associated with polyarthritis in mammals.

The compounds of Formula I are administered preferably orally as their non-toxic salts or esters in the form of powder, granules, capsules, coated or uncoated compressed tablets, or as an aqueous suspension or solution. They may also be administered parenterally as a sterile aqueous solution of their non-toxic salts. Compounds that are especially useful include the a,mdihalo-p-cycloalkyl-phenylacetic acids, a,0-dihalo-pbiphenylylacetic acids, a,m-dihalo-p-lower alkylphenylacetic acids. The preferred compounds of this invention are a,m-dichloro-p-cyclohexyl-phenylacetic acid of Formula V v Q v its lower alkyl esters, and its non-toxic salts; they are administered preferably orally ina dose range of 0.1 mg. to 10 mg. per kg. of body weight. The acute oral toxicity of the preferred compounds are relatively low.

The starting materials for producing the substituted a-halophenyl acetic acids according to Formula II are lower alkyl esters of the corresponding substituted phenylglycolic acid in which R is lower alkyl (C to C cycloalkyl (C to C phenyl, halophenyl, nitrophenyl, trifluoromethylphenyl, cyanophenyl, or methylsulfonylphenyl; R is hydrogen or lower alkyl; R is lower alkyl, and R is halogen, nitro, cyano, trifluoromethyl, methylsulfonyl, or hydrogen (when R is substituted phenyl). The substituted phenylglycolic acid lower alkyl esters of Formula Vll are prepared by the method disclosed in copending patent application Ser. No. 767,058 from the lower alkyl esters of the corresponding substituted phenylglyoxylic acid of Formula Vl either by catalytic hydrogenation when R is hydrogen, or by reaction with a lower alkyl Grignard reagent when R is lower alkyl, as illustrated by the following equation:

.V VII When R is nitro, it is preferable to reduce the lower alkyl ester of Formula VIII of the substituted mnitrophenylglycolic acid with sodium borohydride in methanol to obtain the corresponding lower alkyl ester of Formula IX of a substituted m-nitrophenylglycolic acid. This procedure is illustrated by the following equation:

NaBIIi I 111- (l-COOR 111- CHCOOR I N0! N0;-

vnt 1X Substituted m-fluorophenylglycolate esters of Formula XIII are also obtained by catalytic hydrogenation of the corresponding substituted m-nitrophenylglycolate esters of Formula X to give the substituted maminophenylglycolate esters of Formula XI which, after conversion to the diazonium fluoroborate of Formula XII are thermally decomposed to the substituted m-fluorophenylglycolate esters of Formula XIII as shown in the following equations;

OH OH I Hi HNO Rr- C-COOR R C-COOR I I HBF4 Ra Ra NO: NH:

X XI

OH OH heat Rr- (II-COOK R1- 'COOR R R3 NQBF-I F XII XIII As stated above, the substituted phenylglyoxylic acid lower alkyl esters of Formula VI are produced according to the method of copending Patent application Ser. No. 767,058 by reacting an alkylbenzene, a cycloalkylbenzene, or a biphenyl of Formula XIV with a lower alkyl oxalyl chloride of Formula XV in the presence of aluminum chloride. The resulting lower alkyl esters of the p-alkyl, p-cycloalkyl, of p-biphenylylglyoxylic acids of Formula XVI may be halogenated according to the method described in said. patent application Ser. No. 767,058, or they may be nitrated with fuming nitric acid to about 0C. to produce respectively the corresponding lower alkyl esters of a substituted mhalophenylglyoxylic acid of Formula XVII or a substituted m-nitrophenylglyoxylic acid of Formula IX according to the following equations:

XVI

I-INOa XVI Additional variations in R are obtained by reacting a lower alkyl ester of a substituted mhalophenylglyoxylic acid of Formula XVII as follows:

a. with cuprous cyanide in quinoline at about C.

to produce a lower alkyl ester of a substituted mcyanophenylglyoxylic acid of Formula XVIII:

IL c 1| Ri- (/COOR R1 CCOOR Hal CN XVII XVIII II 1 II R1- C-COOR T R1 C-COOR 0 F3 XVI I XIX c. with cuprous methanesulfinate in quinoline at about 150C. to produce a lower alkyl ester of the substituted m-methylsulfonlphenyI-glyoxylic acid of Formula XX:

Gus OgClh I CIIsSOz The substituted phenylglycolic acid lower alkyl ester of Formula VII is reacted with a phosphorus trihalide. phosphorus pentahalide, phosphous oxyhalide, sulfurylhalide, thionyl halide, or sulfur halide to produce a substituted a-halophenylacetic acid lower alkyl ester of Formula XXI in which Hal is F, Cl, Br, or I.

([)H IiIBI I R3 I R3 R2 R2 VII XXI The ester of Formula XXI is heated with acetic acid containing the corresponding hydrogen halide to give a substituted a-halophenylacetic acid of Formula II.

Reaction of'the lower alkyl ester of a substituted a-halophenylacetic acid of Formula XXI with ammonia or a lower alkylamine leads to a substituted a-halophenylacetamide of Formula XXIII in which R is hydrogen or lower alkyl, and R is hydrogen or lower alkyl.

' IIIaI llial l R3 3 R R XXIII The substitued a-fluorophenylacetic acid derivatives of Formula XXV are also obtained from the corresponding wiodo, a-bromo, or a-chlorophenylacetic acid derivatives of Formula XXIV by reaction with potassium fluoride at about I30200C.

I Br l KF I P (]]COOR R1- C-COOR l a a R2 XXV II, their salts of Formula XXII, or amides of Formula XXIII, on their lower alkyl esters of Formula XXI may be reacted with various nucleophilic reagents to replace the a-halogen group. In particular sulfurcontaining nucleophilic reagents are used such as alkali hydrosulfides MSH, alkali sulfides M S, alkali thiolalkanoates MSCOR, alkali thiocyanates MSCN, alkali sulfites M 50 alkali thiosulfates M 880 alkali alkanesulfinates M SO- R, alkali alkylmercaptides MSR. With excess alkali hydrosulfide a mixture of a substituted a-mercaptophenylacetic acid derivative of Formula XXVI and the corresponding substituted a,a'-dithiodiacetic acid derivative of Formula XXVII are produced. The mercaptan and the disulfide may be separated by fractional crystallization of their salts. Reduction of the disulfide with zinc amalgam and dilute sulfuric acid produces the mercaptan. Oxidation of the mercaptan with dilute iodine solution gives the disulfide.

R1-ta-o 00M XXVI Hal l NaS H R1 (J C0Oll/[ R3 R2 R2 XXII Ra Ri- +C 00M s l s l 3 R2 XXYII Reaction of a substituted a-halophenylacetic acid derivative of the Formulas XXI, II, XXII, or XXIII with thiourea at elevated temperatures, for instance, in boiling ethanol produces a 5-substituted-2-imino-4- oxothiazolidine of Formula XXVIII:

S NII Hal thiourea R3 R3 R2 2 XXI v XXVIII Hydrolysis of the imino compound of Formula XXVIII with-hydrobromic acid in glacial acetic acid leads to a 5-substituted-2,4-dioxothiazolidine of Formula XXIX:

The substituted oz-halophenylacetic acids of Formula XXVIII XXIX lfilHgHal Hal S-C-NH thiourea 1 R1- (ll-COOK 111- -(IICOOH R3 I R3 R2 R2 11 XXX Reaction of a substituted a-halophenylacetic acid derivative of the Formulas XXI, XXIII, II, or XXII with an alkali lower alkylmercaptide produces a substituted a-lower alkylthiophenylacetic acid derivative of Formula XXXI in which R is a lower alkyl with I to 8 carbon atoms.

' XXXI Reaction of a substituted a-halophenylacetic acid derivative of the Formulas XXI, II, XXII, or XXIII with an alkali lower alkyl xanthate produces a substituted a-alkylxanthyl-phenylacetic acid derivative of the Formula XXXII in which R is lower alkyl of 1 to 8 carbons:

XXII

XXXII Reaction of a substituted a-halophenylacetic acid derivative of the Formulas XXI, II, XXIII, or XXII with an alkali thioalkanoate produces a substituted lower alkanoylthiophenylacetic acid of Formula XXXII] in which R is a lower alkyl with l to 8 carbon atoms:

SCOR

Hal i KSCOR R1- |-COOM R1 COOM Ra Rs 2 XXII 2 XXXIII Reaction ofa substituted a-halophenylacetic acid derivative of Formulas XXI, II, XXII, or XXIII with an alkali thiocyanate produces a substituted a-thiocyanophenylacetic acid derivativeof Formula XXXIV:

Hal s ON L s CN 1 R1- J-CooM R1 l-COOM a Ra XXII 2 xxxtv Reaction of a substituted a-halophenylacetic acid derivative of Formula XXI, II, XXII, or XXIII with an alkalicyanide produces a substituted oz-cyanophenylacetic acid derivative of Formula XXXV:

Hal CN KON L Ri- -U-OOOM R1 b-COOM It R3 3 2 xxu 2 xxxv Reaction of a substituted a-halophenylacetic acid derivative of Formulas XXI, II, XXII, or XXIII with an alkali sulfide produces a substituted a,a'-thiodiacetic acid derivative of Formula XXVI:

R: I R; R2

XXII

Reaction ofa substituted a-halophenylacetic acid derivative of Formulas XXI, II, XXII, or XXIII with an alkali sulfite produces a substituted a-sulfophenylacetic acid derivative of Formula XXXVII:

Reaction of a substituted a-phenylacetic acid derivative of Formulas XXI, II, XXII, or XXIII with an alkali thoisulfate produces a substituted a-thiosulfophenylacetic acid derivative of Formula XXXVIII:

Reaction ofa substituted a-halophenylacetic acid derivative of Formulas XXI, II, XXIII, or XXIII with an alkali alkanesulfinate produces a substituted a-alkylsulfonylphenylacetic acid derivative of Formula XXIX. in which R is lower alkyl.

XXXIX drolysis with aqueous-alcoholic alkali hydroxide or alacted in alcoholic or acetone solution with an equivakali carbonate. lent amount of an optically active primary, secondary,

or tertiary amine such as cinchonidine, cinchonine, H quinine, ephedrine, u-methylbenzylamine, secondary ll NazGO: r butylamine, secondary amylamme, and others. The

diastereomeric amine salts produced thereby, are sepa- R rated by fractional crystallization, and each optically XI 6 t active salt lS hydrolyzed with dilute mineral acid to produce the dextro or levo form. respectively, of the sub- 0 l0 stituted phenylacetic acid. Alternatively, the lower Rr-Qt'L-COOH NHRR, alkyl ester of a substituted phenylacetic acid is reacted Hz with an optically active primary or secondary amine such as ephedrine. a-methylbenzylamine. secondary butylamine, and others, to produce a mixture of diasl5 tereomeric substituted phenylacetamides which are 1' separated by fractional crystallization. Each optically l I active phenylacetamide may be hydrolyzed with mineral acid to its respective optically active substituted phenylacetic acid.

I Examples of compounds according to the present insubstltuted a'ammphenylacenc aclds of Formula vention which, however, is not limited thereto, are:

in which R and are hydrogen, y also be P 1. a,m-Dichloro-p-cyclohexylphenylacetic acid pared y hydrogenation of a Substituted phenylglyoxy' 2, iijifi ljichloro-p-cyclohexylphenylacetic acid, solic acid oxime of Formula XLlIl over a platinum catadium Salt lyst. The oxime is obtained from the substituted phenylam Dichloro p cyclohexylphenylaceflc acid m glyoxylic acid of Formula XL with hydroxylamine. thylammonium S3 3. am-Dichloro-p-cyclohexylphenylacetic acid, ethyl ester i H0 1 4. a,m-Dichloro p-cyclohexylphenylacetamide m-c-000n R| @o11oo011 5. a,m-dichloro-p-cyclohexyl-N- isopropylphenylacetamide 1 R2 6. a,m-Dichloro-p-cyclohexyl-a-methylphenylacetic XLIIl XLII acid 7. a-Bromo-m-chloro-p-cyclohexylphenylacetic acid 8. m-Bromo-a-chloro-p cyclohexylphenylacetic acid Dehydration of the substituted phenylglyoxylic acid oxime of Formula XLlll with coiling acetic anhydride 5 Chloro p cyclohexyl a mercaptophenylacenc leads to a substituted benzonitrile of Formula XLlV 1O m Chloro p cyclohexyl a acetomercapto which, with a lower alkyl Grignard reagent, produces l a substituted phenyl alkyl ketone of Formula XDLV, in Hpheny zi g which R is lower alkyl. The latter compound with am henylacetic acid monium chlorideand sodium cyanide produces a cya- 2 1 t l h nohydrin of Formula XLVl which, upon acid hydroly- 1 m ch 0m p cyclohexyl a me by sulfonylp enyla sis yields a substituted 0: aminophenylacetic acid of cetic acid Formula XL, in which R3 is a lower alkyl l356$-chloro-p-cyclohexyl-a-th1ocyanophenylacetic l4. m-Chloro-p-cyclohexyl-a-aminophenylacetic NOH acid RFQCLCOOH A020 E li; l5. r3-chloro-p-cyclohexyl-a-acetaminophenylacetic ac1 R2 R2 5O 16. a,a-Di(m-chloro-p-cyclohexylphenyl)-a,a'-

XLIII XLIV dithiodiacetic acid 17. a-Chloro-p-cyclohexyl-m-nitrophenylacetic acid NH Cl E His 04 18. a-Chloro-m-cyano-p-cyclohexylphenylacetic Rr- C=O R1 -CN l NaCN act Ra Ra R2 19. a-Chloro-p cyclohexyl-m-trifluoromethylphenylacetic acid LXV LXVI 20. am-Dic hloro-p-cyclopentylphenylacetic acid 1 a,m-Dichloro-p-cycloheptylphenylacetic acid I OH 22. 5-(m-Chloro-p-cyclohexylphenyl)-2,4-

| Rs dioxothiazolidine 23. 5-(m-Chloro-p-cyclohexylphenyl)-5-methyl-2- 1mmo-4-oxoth1azolid1ne 1 24. 2-(m-Chloro-p-cyclohexylphenyl)-2-imino-4- The substituted phenylacetic acids of this invention oxothiazolidine and their carboxy derivatives areracemic, and may be 25. 01,01-Di-(m-chloro-p-cyclohexylphenyl)-oz,a'- resolved into their optical isomers by standard procethiodiacetic acid dures. Preferably a substituted phenyla cetic acid is re- 26. 01,0'-Dichloro-p-biphenylacetic acid 27. a,m-Dich10ro-p-isobutylphenylacetic acid 28. m-Chloro-p-cyclohexyl-a-sulfophenylacetic acid,

. sodium salt 29. m-Chloro-p-cyclohexyl-a-thiosulfophenylacetic acid, sodium salt 30. m-Chloro-p-cyclohexyl-oz-cyanophenylacetic acid, sodium salt 31. m-chloro-p-cyclohexyl-aethylxanthylphenylacetic acid, ethyl ester 32. o-Bromo-a-chloro-p-biphenylacetic acid 33. a,m-Dichloro-p-sec-amylphcnylacetic acid 34. a-Chloro-o'-trifluoromethyl-p-biphenylacetic acid 35. a-Chloro-o'-nitro-p-biphenylacetic acid 36. a-Chloro-o'-cyano-p-biphenylacetic acid 37. m-Chloro-p-cyclohexyl-a-fluorophenylacetic acid 38. o-Chloro-a-mercapto-p-biphenylacetic acid 39. m-chloro-p-isobutyl-a-mercaptophenylacetic acid.

40. a,m-Dichloro-p-cyclohexylphenylacetic acid,

benzyl ester.

41. a,m-Dichloro-p-cyclohexylphenylacetic acid.

menthyl ester.

42. a,m-Dichloro-p-cyclohexylphenylacetic acid, cy-

clohexyl ester.

43. am-Dichloro-p-cyclohexylphenylacetic phenyl ester.

44. a,m-Dichloro-p-cyclohexylphenylacetic acid, di-

ethylaminoethyl ester.

45. a,m-Dichloro-p-cyclohexylphenylacetic piperidinoethyl ester.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following examples serve to illustrate the present invention without, however, limiting the same thereto.

EXAMPLE 1 a,m-Dichloro-pcyclohexylphenylacetic acid ethyl ester.

acid,

acid,

1 OQCHCOOCQIB 221.75 g. (0.747 mole) of the ethyl ester of m-chloro-pcyclohexylphenylglycolic acid are stirred with 106.67 g. (0.895 mole) of thionylchloride at room temperature for 24 hours and then heated to reflux for 6 hours. The cold reaction mixture is poured into 1,125 ml. of icecold water with stirring. The mixture is extracted with 800 ml. of ether. The ethereal solution is washed with 450 ml. of cold saturated sodium hydrocarbonate solution followed by washing twice, each time with 250 ml. of cold water. The ethereal solution is dried over anhydrous sodium sulfate and filtered. The solvent is removed by distillation under reduced pressure. Yield: 230.7 g. (97.9 percent) of liquid, b.p. 118-122 C./0.05 mm. Hg. T.L.C. (silica): CH 4 HCOOET21 HCOOH, R 0.86, 0.70 (trace).

Anal. Calculated for C H Cl O 60.96 C; 6.40 H;

22.49 Cl. Found: 60.96 C; 6.46 H; 21.56 C1.

EXAMPLE 2 a,m-Dichloro-p-cyclohexylphenylacetic acid 52.5 g. (0.167 moles) of the ethyl ester of mmdichloro-p-cyclohexylphenylacetic acid and 160 ml. of glacial acetic acid containing 40 ml. of 37 percent hydrochloric acid are refluxed for 20 hours. The mixture is concentrated under reduced pressure to give a gummy residue (47.1 g.). The latter material is dissolved in 300 ml. of n-hexane, washed with ice-cold water ml. total), dried over Na SO (sodium sulfate), and filtered. The hexane is removed to give 47.2 g. of product. TLC (silica): 5 C 11 4 HCOOEt: l HCOOH, R 0.64, 0.49 (trace).

EXAMPLE 3 a,m-Dichloro-p-cyclohexylphenylacetic acid sodium salt III

A solution of 12.4 g. of sodium bicarbonate in ml. H O is added dropwise to a stirred solution of 47.1 g. (0.164 moles) of a,m-dichloro-p-cyclohexylphenylacetic acid in cc. of methanol. The solvent is removed in vacuum, and the residue is dried by repeated distillations with anhydrous ethanol. The crystalline residue is triturated with ether (100 cc.), collected on a filter, and washed with ether. After drying in a vacuum desiccator overnight, the crystalline product weighs 41.6 g. (91.3 percent). TLC (silica): 5 C l-I :4 HCOOEt:1 HCOOl-l, R, 0.62, 0.49 (trace) Anal. Calculated for C H Cl o Naz 54.38 C; 4.89 H; 22.93 Cl.

Found: 54.10 C; 5.18 H; 21.75 Cl.

EXAMPLE 4 Diethylammonium salt of a,m-dichloro-p-cyclohexylphenylacetic acid a Y C on-c o ommo ttm Anhydrous diethylamine (0.11 moles) is added dropwise to a stirred solution of a,m-dichloro-p-cyclohexylphenylacetic acid (0.10 moles) in 100 ml. of n-hexane at 0 C. The precipitated diethylammonium salt is collected on a filter, washed with n-hexane, and dried in a vacuum desiccator. Yield: 34 g., white crystals. M.P. 1091 15 C.

Anal. Calculated for C H CI NO 60.00 C; 7.55 H; 3.89 N; 19.68 Cl.

Found: 60.23 C; 7.61 H; 3.79 N; 19.24 '70 Cl.

15 EXAMPLE a,m-Dichloro-p-cyclohexyl-N- isopropylphenylacetamide 5 g. (0.016 moles) of the ethyl ester of a,m-dichloro-pcyclohexylphenylacetic acid are stirred with 5.5 ml. of anhydrous isopropylamine and Linde 4A molecular sieve for 16 hours at room temperature. The reaction mixture is filtered and excess isopropylamine is removed in vacuum. The residue is taken up in ether and washed three times, each time with ml. of 10 percent hydrochloric acid. The ether layer is dried over sodium sulfate, filtered, and the ether is removed. The residue is triturated with n-hexane to precipitate the amide, white crystals, M.P. 85-87 C. TLC (silica): 5 C H z4 l-lCOOEt: lYHCOOH, R 0.75

Anal. Calculated for C l-l Cl NOz 62.20 C; 7.06 H; 4.27 N; 21.60 Cl.

Found: 61.49 C; 6.98 H; 4.21 N; 20.64 Cl.

QQM E. 6

oi-Bromo-m-chloro-p-cyclohexylphenylacetic ethyl ester acid To 15.0 g. (0.0476 moles) of m-chloro-p-cyclohexylphenylglycolic acid ethyl ester there are added slowly with stirring at 4050 C. 23 g. (0.053 moles) of phosphorus pentabromide. The mixture is stirred at room temperature for 16 hours, then diluted with 70 ml. of petroleum ether, and poured into 125 ml. of ice-cold water. The organic phase is separated, washed with saturated aqueous sodium hydrogen carbonate solution, dried over anhydrous sodium sulfate, filtered and the solvent removedin vacuo to leave 12.1 g. (70.8 percent) of crude product. Distillation of the residue gives 8.] g. (47.4 percent) of a pale yellow liquid, b.p. l57l6l C./0.l0 mm. Hg. TLC (silica): 5 C H :4 HCOOEt:l HCOOH, R 0.90

Anal. Calculated for c H BrClO:

Calculated: 53.42 C; 5.60 H; 32.08 Cl Br Found: 53.42 C; 5.42 H; 31.6 Cl Br EXAMPLE 7 Diethylammonium salt of a-bromo-m-chloro-pcyclohexylphenylacetic acid The salt is prepared from a-bromo-m-chloro-pcyclohexylphenylacetic acid ethyl ester by treating the EXAMPLE 8 Ethyl ester of a,m-dichloro-p-cyclohexyl-amethylphenylacetic acid 68.4 g. (0.330 moles) of phosphorus pentachloride are slowly added with stirring to 92.4 g. (0.300 moles) of m-chloro-p-cyclohexyl-oz-methylphenylglycolic acid ethyl ester. The mixture is allowed to warm spontaneously and is stirred at room temperature for 16 hours. The cold reaction mixture is diluted with 340 ml. of petroleum ether and stirred with 500 ml. of ice water. The organic phase is separated and is then washed with cold 10 percent sodium bicarbonate solution (twice with ml. each time) followed by a water wash. The organic phase is dried over sodium sulfate, filtered, and the solvent is removed under reduced pressure to give 86.3 g. (87.5 percent) of the above ester, b.p. l55-l 58 C./0.35 mm. Hg. TLC (silica): 5 CH 4 HCOOEt:l HCOOH, R 0.90, 0.71 (trace) Anal. Calculated for C H Cl O 62.00 C; 6.73 H; 21.53 Cl Found: 62.02 C; 6.43 H; 21.62 Cl.

EXAMPLE 9 Sodium salt of a-chloro-m-nitr0-p-cyclohexylphenylac etic acid The salt is prepared in the same manner as described in Example 3v except that the starting material is ninitro-p-cyclohexylphenylglycolic acid ethyl ester. The latter is obtained by nitration of p-cyclohexylphenylglyoxylic acid ethyl ester with fuming nitric acid at 0 C. and reduction with sodium borohydride.

EXAMPLE 10 Sodium salt of a-chloro-m-trifluoromethyl-pcyclohexylphenylacetic acid (ill The salt is prepared in the same manner as described in Example 3 except that the starting material is pcyclohexyl-m-trifluoromethylphenylglycolic acid ethyl ester. The latter is obtained from the corresponding mbromo-p-cyclohexylglyoxylate ester with trifloromethyl iodide and copper powder in dimethylformamide at about 150 C. followed by catalytic hydrogenation over platinum at 25 C. and 3 atm. pressure.

EXAMPLE 1 1 The sodium salt of oz-chloro-m-cyano-p-cyclohexylphenylacetic acid EXAMPLE 12 Y Sodium salt of a,o'-dichloro-p-biphenylacetic acid Cl Q- The salt is prepared in the same manner as described in Example 3 except that the starting material is o'-chloro-p-biphenylglycolic acid ethyl ester.

EXAMPLE 13 Sodium salt of o-bromo-a-chloro-p-biphenylacetic acid.

01 QQ-CHC O ONa The salt is prepared in the same manner as described in Example 3 except that the starting material is o-bromo-p-biphenylglycolic acid ethyl ester.

EXAMPLE 14 Sodium salt of a,m-dichloro-p-isobutylphenylacetic acid or wmncrrom-Q-nooom The salt is prepared in the same manner as described in Example 3 except that the starting material is mchloro-p-isobutylphenylglycolic acid ethyl ester.

EXAMPLE 15 Sodium salt of biphenylylacetic acid a-ch1oro-o'-trifl uoromethyl-p- The salt is prepared in the same manner as described in Example 3 except that the starting material is o'- trifluoromethyl-p-biphenylglycolic acid ethyl ester.

EXAMPLE l6 5-(m-Chloro-p-cyclohexylphenyl)-2-imino-4- oxothiazolidine @Q-an s NH Cl 230.7 g. (0.732 moles) of the ethyl ester of a,m-dichloro-p-cyclohexylphenyl acetic acid are dissolved in 960 ml. of ethanol. To this solution there are added 66.9 g. (0.878 moles) of thiourea. The mixture is heated under reflux with stirring for 26 hours, whereupon the product precipitates out. The cold reaction mixture is diluted with 2.3 l. of water. The light yellow solid is collected on a filter and washed with 20 percent ethanol. The product is dried at 60 C. in a vacuum to remove most of the water, then stirred with 2 l. of anhydrous ether, collected by filtration, washed with anhydrous ether, and dried at 60 C. in a vacuum. Yield: 145.2 g. (64.3 percent), m.p. 240-242 C.

TLC(silica): 5 toluene: 4 HCOOEt: 1 HCOOH, R, 0.44

Anal. Calculated for C H CINOS: 58.34 C; 5.55 H; 9.07 N; 11.48 Cl; 10.38%

Found: 58.09 C; 5.49 H; 8.22 N; i209 Cl; 10.08%

EXAMPLE l7 5-[m-Chloro-p-cyclohexylphenyl ]-2 ,4- dioxothiazolidine 1 .i. Am 01 15.44 g. (0.05 moles) of S-(nz-chloro-pcyclohexylphenyl)-2-imino-4-oxothiazolidine are refluxed with 200 m1. of 48 percent hydrobromic acid with stirring for 24 hours. The hydrobromic acid is removed by distillation under reduced pressure. The residue is extracted with ether. The etheral solution is washed with water and dried over anhydrous magnesium sulfate. After removing the drying agent and the solvent, the residue is triturated with n-hexane. The white solid which separates is collected by filtration, washed with n-hexane, and dried at 60 C. in a vacuum. Yield: 7.9 g. (51 percent), M.P. 200.5-202.5 C. TLC (silica): 5 CH 4 HCOOEt: 1 HCOOH, R 0.67 Anal. Calculated for C(,',H1 ClNO H; N;

58.15 C: 5.21 H: 4.52 N: 11.44 Cl; 10.35% S 19 Found: 57.89 c; 5.24 H; 4.48 N; 11.96 01;

EXAMPLE l8 a,oz'-Di-m -chloro-p-cyclohexylphenyl -a,a dithiodiacetic acid ll NH l8l.8 g. (0.427 moles) of S-[m-chloro-pcyclohexylphenyl]-2-imino-4-oxothiazolidine, Iliter of 10 percent sodium hydroxide solution, and 325 ml. of 95 percent ethanol are refluxed with stirring for hours. After distilling off the ethanol, the mixture is cooled to room temperature, washed three times with ether, each time with 300 ml. of ether, and acidified with 310 ml. of 6N hydrochloric acid solution (1.86 moles) with stirring in the presence of 700 ml. of ether. The aqueous portion is extracted twice with ether, each time with 400 ml. of ether. The combined ethereal solution is dried over anhydrous magnesium sulfate and filtered. The solvent is removed under reduced pressure leaving the above acid.

EXAMPLE l9 Diethylammonium salt of a,adi-[m-chloro-pcyclohexylphenyl]-a',a'dithiodiacetic acid OQ-imcooa 133 g. (0.199 moles) of crude a,a'-di-[m-chloro-pcyclohexylphenyl]-a,a-dithiodiacetic acid are dissolved in 800 ml. of anhydrous ether. To this solution there are added dropwise with stirring 33.2 g. (0.454 moles) of diethylamine diluted with 30 ml. of anhydrous ether. The mixture is stirred for 3 hours, where:

upon the crude product precipitates out. The solid is EXAMPLE 20 Diethylammonium salt of m-chloro-p-cyclohexyl-amercaptophenylacetic acid OQ-oHooommomm EXAMPLE 2l 5-( m-C hloro-p-cyclohexylphenyl )-2-imino-5-methyl- 4oxothiazolidine Cl Ha 20.0 g. (0.0607 moles) of a,m-dichloro-p-cyclohexyla-methylphenylacetic acid ethyl ester and 5.3 g. (0.0699 moles) of thiourea are dissolved in 30 cc. of dry dimethylformamide and are heated in an oil bath at 105 C. for 24 hours. The dimethylformamide is removed under reduced pressure to leave a gum which upon trituration with water precipitates the crude product, which is collected on a filter, washed with water, and dried under vacuum. The crude product is dissolved in methanol, and diluted with ethyl acetate to give 4.4 g. (22.4 percent) of purified product, m.p. 254-259 C. TLC (silica): 5 CH 4 HCOOEt: l HCOOH, R 0.51

Anal. Calculated for C H CIN OS: 59.52% C; 5.93% H; 10.98% Cl; 9.93% S; 8.68% N Found: 59.34% C; 6.30% H; 10.98% Cl; 10.67% S; 8.44% N EXAMPLE 22 Sodium salt of acetothiophenyl acid m-chloro-p-cyclohexyl-a- SOOCIIS QjQ-dnooom The sodium salt of oz,m-dichl0ro-p-cyclohexylphenylacetic acid (0.050 moles) is reacted with purified sodium thioacetate (0.050 moles) in ml. of anhydrous ethanol at 2580 C. under a nitrogen atmosphere for 4 to 8 hours. The precipitated sodium chloride is filtered off and the filtrate is concentrated to dryness in vacuo at 25 C. to leave the crude product as a residue. The latter is purified by recrystallization or by column chromatography.

EXAMPLE 23 Sodium salt of m-chloro-p-cyclohexyl-a-methylthiophenylacetic acid SCHs The procedure is the same as described in Example 22 except that sodium methylmercaptidc is used in place of sodium thiolacetate.

EXAMPLE 24 Sodium salt of m-chloro-p-cyclohexyl-a-methylsulfonylphenylacetic acid SOzCHa The procedure is the same as described in Example 22 except that sodium methanesulfimate is usedin place of sodium thiolacetate.

EXAMPLE 25 Sodium salt of m-chloro-p-cyclohexyl-a-thiocyanophenylacetic acid SCN The procedure is the same as described in Example 22 except that sodium thiocyanate is used in place of sodium thiolacetate.

EXAMPLE 26 Sodium salt of m-chloro-p-cyclohexyl-a-sulfophenylacetic acid S OsNa The procedure is the same as described in Example 22 except that sodium sulfite is used in place of sodium thiolacetate.

EXAMPLE 27 Sodium salt of m-chloro-pwcyclohexyl-a-thiosulfophenylacetic acid The procedure is the same as described in Example 22 except that sodium thiosulfate is used in place of sodium thiolacetate.

EXAMPLE 28 Sodium salt of m-chloro-p-cyclohexyl-a-ethylxanthylphenylacetic acid The procedure is the same as described in Example 22 except that sodium ethyl xanthate is used in place of sodium thiolacetate.

EXAMPLE 29 Sodium salt of cyanophenylacetic acid m-chloro-pcyclohexyl-a- The procedure is the same as described in Example 22, except that sodium cyanide is used in place of sodium thiolacetate.

EXAMPLE 30 Sodium salt of a,u'-di-(m-chlor0-pcyclohexylphenyl)-a,oz-thiodiacetic acid @Q-t'mcoom The procedure is the same as described in Example 22, except that sodium sulfide (0.025 moles) is used in place of sodium thiolacetate (0.050 moles).

EXAMPLE 3] Hydrochloride of m-chloro-p-cyclohexyl-a-isothioureidophenylacetic acid IIIlI Cl S CNI-I EXAMPLE 32 m-Chloro-p-cyclohexylphenylglyoxylic acid oxime IEIOH m-Chloro-p-cyclohexylphenylglyoxylic acid ethyl ester is hydrolyzed by heating with a 10 percent sodium carbonate solution for 24 hours. The cold reaction mixture is washed with ether, acidified with cold dilute hydrochloric acid, and extracted with ether. Removal of the ether leaves the carboxylic acid compound. 38.5 g. (0.144 moles) of m-chlor-p-cyclohexylphenylglyoxylic acid, 37.0 g. (0.45 moles) of sodium acetate, and 16 g. (0.23 moles) of hydroxylamine hydrochloride are stirred in 300 ml. of 50 percent aqueous ethanol at room temperature for 24 hours. The mixture is diluted with water, brought to a'pl-I of 4.0 by the addition of hydrochloric acid and extracted three times with ether.

PHARMACEUTICAL COMPOSITIONS CONTAINING THE COMPOUNDS ACCORDING TO THE PRESENT INVENTION I such as in the form of solutions, sirups, emulsions, sus- The combined ether extracts are dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. On trituration with cyclohexane, 12 g. (29 12 percent) of the oxime are obtained, M.P.

l69.5 C. with decomposition. The oxime gives a red coloration with ferric chloride solution. On concentrating the filtrate and adding heptane, an additional amount of the oxime is obtained, 17.3 g. (42.5 percent); total combined yield: 29.3 g. (72 TLC (silica): 5 CH 4 HCOOEt: 1 HCOOH, R 0.46

Analysis: Calculated for C H ClNO 59.68% C; 5.72% H; 12.59% Cl; 4.97% N Found: 60.10% C; 5.80% H; 11.88% Cl; 4.89% N EXAMPLE 33 a-Amino-m-chloro-p-cyclohexylphenylacetic acid NOH 17.8 g. (0.0633 moles) of m-chloro-p-cyclohexylphenylglyoxylic acid oxime are dissolved in 90 ml. of methanol. Platinum oxide catalyst (0.5 g.) and 12 ml. of 6N hydrochloric acid (0.072 moles) are added, and the mixture is shaken with hydrogen at an initial pressure of 55 psi. Total uptake is 98 percent of theory in 4 hours. The catalyst is filtered off and the solvent is distilled off under reduced pressure. The residue is triturated with water containing 5.9 g. (0.072 moles) of sodium acetate, filtered, and washed several times with water. The precipitate is stirred with anhydrous ether,

filtered, and washed with ether. Yield: 15 g. (89 per- V2 HCl:

pensions, dispersions, fruit juices and the like is also possible.

Such powders, granules, and mixtures to be used in the preparations of tablets and other shaped and/or compressed preparations may be diluted by mixing and milling with a solid pulverulent extending agent to the desired degree of fineness or by impregnating the already milled, finely powdered, solid carrier with a suspension of said compounds in water or with a solution thereof in an organic solvent such as ethanol, methanol, acetone, and others and then removing the water or solvent.

When preparing tablets, pills, dragees, and the like shaped and/or compressed'preparations, the commonly used diluting, binding, and disintegrating agents, lubricants, and other tableting adjuvants are employed, provided they are compatible with said substituted phenylacetic acid compounds. Such diluting agents and other excipients are, for instance, sugar, lactose, levulose, starch, bolus alba; as disintegrating and binding agents,

gelating, gum arabic, yeast extract, agar, tragacanth,

methyl cellulose, pectin; and as lubricants stearic acid, talc, magnesium stearate, and others.

The compounds according to Formula I may also be administered parenterally, preferably in the form of their water soluble salt, for instance, in sterile isotonic aqueous solution.

Administration in the form of suppositories is, of course, also possible:

Such pharmaceutical compositions are prepared according to pharmaceutical compounding methods as they are conventionally used in the art.

The following examples of pharmaceutical composi' tions containing the active compounds of Formula 1, their esters and/or their salts, serve to illustrate the preparation thereof without, however, being limited thereto.

EXAMPLE 34 sules. Each gelatin capsule thus contains 25 mg. of theactive substituted phenylacetic acid ester of this invention.

EXAMPLE 35 g. of the diethylammonium salt of a,m-dichlorop-cyclohexylphenylacetic acid,v

1200 g. of starch (direct compression grade) as sold by the firm A. E. Staley Mfg. Co. of Decatur, 111. under the trademark STAREX, and

10 g. of magnesium stearate are thoroughly blended and compressed to give tablets, each containing 25 mg. of the active ingredient.

EXAMPLE 36 The mixture of Example 35 is compressed to biconcave dragee cores, each containing 25 mg. of the active ingredient. The cores are then provided in a manner known in the compounding art with an enteric shellac coating.

Of course, other dosage forms than capsules and tablets can be prepared by using well known compounding techniques and the a,m-dichloro-p-cyclohexylphenylacetic acid compounds used in Examples 34 to 36 can be replaced by other substituted phenylacetic acid compounds according to the present invention.

PHARMACOLOGICAL TESTS A brief description of the pharmacological tests conducted with the compounds according to the present invention are given below:

Carageenan Paw Edema Of the substances used to induce local irritation, carrageenan was selected since most known non-steroidal anti-inflammatory agents inhibit this inflammation.

Ten male rats per dose group (120-150 g.) were given one-half of the test material orally. Thirty minutes later, the remainder of the dose was given and 0.2 ml. of a 1 percent carrageenan solution was injected subdermally into the plantar surface of the hind paw. Each paw is marked as a consistent anatomical site, then immersed in a mercury bath to that point. The mercury bath is connected to a pressure transducer and the volume of displacement is read directly on a recorder. Three hours after drug administration, the hind I paw volume is measured again. The increased volume is anindex of edema. Treated groups are compared to a placebo-treated group to calculate the percent inhibition of edema. Filter Paper Granuloma This assay was used to evaluate anti-inflammatory agents and to determine the lowest dose which produces significant inhibition of granuloma growth. This assay has the advantage of being semi-acute (4 to 7 days). The usual end point involves obtaining the wet weight as well as the dry weight of the granuloma.

Small discs of filter paper saturated with carrageenan were placed subcutaneously in each rat on the first day of the study. Test compound was administered orally on a b.i.d. basis on Day 1 to Day 4. On Day 5, a single dose was given in the morning and the animals were sacrificed in the afternoon. Both filter paper discs were removed and trimmed of extraneous tissue and then weighed. After drying in an oven over the weekend, the dry weight was obtained. Activity was determined by the difference in granuloma weight between a placebotreated control group and the drug-treated groups. Randall-Selitto Analgesia Test In accordance with the Randall-Selitto test for measuring the pain threshold, the pressure needed on a metal plunger to give a pain response in a rat when the plunger is placed in the yeastinflamed hind paw of a rat is measured. Following measurement of control pain threshold, yeast was injected into the paw and the test compound was given orally. The pain threshold was measured at hourly intervals and compared to a placebo-treated control group. Anti-Pyretic Assay Brewers yeast was injected subcutaneously in rats and rectal temperatures were obtained at the end of hours. Those rats (10 per group) having a significant fever were given test compounds and rectal tempera- 5 tures were measured at hourly intervals for 2 to 3 hours. (A positive response occurs when rectal temperature decreases by 1 C. or more). Phenylquinone Analgesia Mice were pre-treated orally with test compound and then given 1.25 mg./kg. of phenylquinone i.p. to produce a series of writhes" (severe intestinal contractions). The number of writhes was recorded. The percent decrease was calculated from the incidence of writhes in a placebo-treated control group. Ultra-violet Erythema in Guinea Pigs Erythema associated with inflammation was used in the assay. Restricted areas of guinea pig were exposed to a controlled ultra-violet light and after 2 hours the exposed areas were graded for the extent of erythema. Polyarthritis in Rats Twelve rats per dose group were treated (b.i.d.) starting the day before injection of adjuvant. Paw volumes were measured for both hind paws on several days during and following drug treatment. Drug was given for a period of days. The pain volume was compared to an untreated control group to determine volume increase. Drug action was calculated as the percent decrease in paw volume (inflammation) as compared to an adjuvant-treated control. Gross signs of inflammation were scored on a weekly basis and drug action calculated as a decrease in total score. Body weights were recorded at intervals. Acute Toxicity Groups of ten (10) male mice (18g. to 24 g.) were treated with various doses of drug and were observed for nine days following drug administration. Food and water were delivered ad lib. The drug to be tested was prepared as a water suspension using one drop of Tween 80" per 10 ml. and administered orally as a single dose (10 ml./kg.). The control group received the vehicle only (10 ml./kg.). The lethal dose (LD which is the dose of drug required to kill 50 percent of the animals tested, was determined by the Litchfield and Wilcoxon method.

The following compounds were tested Sodium salt of a, m-dichloro-p-cyclohexylphenylacetic acid, designated as 539A;

The test results are given in the following Table wherein the following legends were employed:

PQW Phenylquinone writhing RSA Randall-Selitto Analgesia CPE Carrageenan Paw Edema UVE Ultra-Violet Erytherna FPG Filter Paper Granuloma -Continued Oct. 10, 1968 under the title p-CYCLOALKYL- AP Anti-Pyresis PHENYLGLYCOLIC ACID AND DERIVATIVES 11? PNain ghrifhold IT I THEREOF". Said application Ser. No. 767,058 and its n g s g g i g contents thus are incorporated by reference into the I Percentage Inhibition 5 present application.

Polyarthritis percent avg. inhibition at n1g./kg./day FPG at mgJkg/day Acute UVE Non- Secondtoxicity, Coni- Dose, IQW CPE RS Al Injected injected ary %J, %l Ll)5|y. pound mg./kg. Route 7 1 EDso %J, %TPT #P/T #P/T ED50 hindpaw hindpaw lesions \vcL dry rug/kg.

539A 1 P.O.

l P.O. 30. 3.125 P.O.

R0; 6. 25 P.O. 10 P.O. 12.5 P.O. P.O. P.O. P.O. P.O. 100 P.O.

528A 5 P.O. 10 P.O. 25 P.O. 50 P.O. 100 P.O.

531A so P.O. 32 1/8 .Q. 100 P.O. 19.9 23 1/8 A 34.04356 44.7-13.8 30.3-43.6 r 1Z,000 200 P.O. 51 6/8 A r V t 530 50 P.O. 100 P.O. 200 P.O.

529.- 50 P.O. 100 P.O. 200 P.O.

541 6.25 P.O. 12.5 P.O. 25 P.O. P.O.

CLINICAL UTILITY The compounds of Formula I, their esters, and their salts have proved to be potent anti-inflammatory drugs with a high analgesic and antipyretic activity. They are administered to patients suffering from rheumatoid arthritis, rheumatoid spondylitis, osteoarthritis, acute gouty arthritis, bursitis, and other arthritic disorders. The esters of said compounds and especially the ethyl ester of a, rn-dichlorocyclohexylphenylacetic acid have proved to be especially useful as they are better tolerated and not as irritating on the gastrointestinal tract as the free acids.

As stated hereinabove, the compounds of Formula I, their esters, and their salts are preferably administered in a dose of 0.1 mg./kg. to 10 mg./kg. given once to four times daily. Thus the actual dose may vary between about 5 mg. and about 500 mg. once to four times daily which dose is preferably administered orally.

As stated hereinabove, the starting materials, i.e. the lower alkyl esters of substituted phenylglycolic acids as well as of substituted phenylglyoxylic acids are prepared according to processes described in copending application Ser. No. 767,058 of one of the Applicants of the present application, which application was filed We claim:

1. A substituted phenylacetic acid compound selected from the group consisting of a, m-dihalo-P-lower alkylphenylacetic acid and its substantially non-toxic ester or salt, said ester being selected from the group consisting of lower alkyl, cyclo-lower alkyl, menthyl, phenyl, phenyl lower alkyl, lower alkyl phenyl, di-lower alkylamino lower alkyl, piperidino lower alkyl, piperazino lower alkyl, and pyrrolidino lower alkyl esters.

2. The substituted phenylacetic acid compound of claim 1, said compound being selected from the group consisting of a, m-dihalo-p-lower alkylphenylacetic acid and its substantially non-toxic ester or salt. said ester being selected from the group consisting of ethyl, benzyl, menthyl, cyclohexyl, phenyl, diethylaminoethyl, and piperidinoethyl esters.

3. The compound of claim 1, which is m-chloro-pisobutyl-a-mercaptophenylacetic acid.

4. The compound which is a, isobutylphenylacetic acid.

5. The compound which is a,m-dichloro-p-secamylphenylacetic acid.

m-dichloro-p- 

1. A SUBSTITUTED PHENYLACETIC ACID COMPOUND SELECTED FROM THE GROUP CONSISTING OF A, M-DIHALO-P-LOWER ALKYLPHENYLACETIC ACID AND ITS SUBSTANTIALLY NON-TOXIC ESTER OR SALT, SAID ESTER BEING SELECTED FROM THE GROUP CONSISTING OF LOWER ALKYL, CYCLOLOWER ALKYL; MENTHYL, PHENYL, PHENLY LOWER ALKYL, LOWER ALKYL PHENYL, DI-LOWER ALDYLAMINO LOWER ALKYL, PIPERIDINO LOWER ALKYL, PIPERAZINO LOWER ALKYL AND PYRROLIDINO LOWER ALKY ESTERS.
 2. The substituted phenylacetic acid compound of claim 1, said compound being selected from the group consisting of Alpha , m-dihalo-p-lower alkylphenylacetic acid and its substantially non-toxic ester or salt, said ester being selected from the group consisting of ethyl, benzyl, menthyl, cyclohexyl, phenyl, diethylaminoethyl, and piperidinoethyl esters.
 3. The compound of claim 1, which is m-chloro-p-isobutyl- Alpha -mercaptophenylacetic acid.
 4. The compound which is Alpha , m-dichloro-p-isobutylphenylacetic acid.
 5. The compound which is Alpha ,m-dichloro-p-sec-amylphenylacetic acid. 